1. Field of the Invention
The present invention relates to an engine compartment cover for a work machine which comprises left and right-hand side covers and an upper hood, and serves to demarcate an engine compartment, and more particularly, to an engine compartment cover provided with a ventilation opening for allowing air to circulate inside the engine compartment.
2. Description of the Related Art
For example, a tractor, bulldozer, or the like, which is one type of a work machine, comprises an engine and power train mounted on a main frame equipped with an undercarriage, and is also provided with an operator cab in which an operator (driver) can sit.
Furthermore, the engine is covered by an engine compartment cover, and this engine compartment cover comprises a pair of left and right-hand side covers for covering the sides of the engine, and a hood for covering the top of the engine, and together with a front grille, and the like, this engine compartment cover serves to demarcate the engine compartment.
Moreover, in the aforementioned engine compartment cover, a ventilation opening is provided in order to allow air to circulate inside the engine compartment, with the object of cooling the engine, and the like, a composition being adopted, for example, wherein external air is taken into the engine compartment via the front grille positioned on the front side thereof, and air is discharged from the engine compartment to the outside, via a ventilation opening provided in the hood of the engine compartment cover.
In a composition in which a ventilation opening is provided in the hood of the engine compartment cover, as described above, the noise generated by the sound of the engine during operation travels from the inside of the engine compartment, through the aforementioned ventilation opening, and is radiated upwards from the engine compartment cover.
On the other hand, in an earthmoving vehicle, such as a tractor, bulldozer, or the like, if the engine is mounted to the front side of the operator cab, then the hood of the engine compartment cover is laid out in such a manner that it only reaches to a position below the operator's line of sight, in order to ensure the field of vision of the operator sitting in the operator cab.
Therefore, since the engine noise is radiated upwards from the ventilation opening provided in the hood of the engine compartment cover as described above, then the noise to which the operator sitting in the operator cab is exposed, in other words, the noise at the level of the operator's ears, is very loud, and therefore problems occur in that the working efficiency of the operator declines markedly due to the loss of quietness in the operator cab.
The present invention was devised with the foregoing in view, an object thereof being to provide an engine compartment cover for a work machine whereby the noise reaching the operator's ear level caused by engine noise passing through the engine compartment cover is suppressed as far as possible, thereby making it possible to enhance the level of quietness in the operator cab.